noise.rs

use minifb::{Key, ScaleMode, Window, WindowOptions};

const WIDTH: usize = 1280;
const HEIGHT: usize = 720;

fn main() {
    let mut noise;
    let mut carry;
    let mut seed = 0xbeefu32;

    let mut buffer = vec![0u32; WIDTH * HEIGHT];

    let mut window = Window::new(
        "Noise Test - Press ESC to exit",
        WIDTH,
        HEIGHT,
        WindowOptions {
            resize: true,
            scale_mode: ScaleMode::UpperLeft,
            ..WindowOptions::default()
        },
    )
    .expect("Unable to create the window");

    window.set_target_fps(60);

    let mut size = (0, 0);

    while window.is_open() && !window.is_key_down(Key::Escape) {
        let new_size = window.get_size();
        if new_size != size {
            size = new_size;
            buffer.resize(size.0 * size.1, 0);
        }

        for pixel in buffer.iter_mut() {
            noise = seed;
            noise >>= 3;
            noise ^= seed;
            carry = noise & 1;
            noise >>= 1;
            seed >>= 1;
            seed |= carry << 30;
            noise &= 0xFF;

            *pixel = (noise << 16) | (noise << 8) | noise;
        }

        window
            .update_with_buffer(&buffer, new_size.0, new_size.1)
            .unwrap();
    }
}